Tuesday, 30 August 2011

As I sat in my hotel room on the morning before my final visit of the trip, I reflected on what I had seen and what I had learned. Mob grazing is a catch-all description for many subtly varied ways of high-density grazing. Most were successful, in terms of improving plant recovery rates and increasing stocking rates, as well as making pastures more drought-tolerant (and better able to stand heavy rainfalls too!)

The majority of practitioners were also practicing holistic management, focusing on its three entwined measures of success, namely financial, environmental and social measures.

However, there were still certain things eating away at me. The main one was weed control. Would UK pastures, in our non-brittle environment, revert to a mass of inedible weeds in a few years? What type of management strategy would need to be adopted to avoid this? Would we be forced to top our grassland with mowers to prevent this or could cattle alone be used?

If weeds did invade, how easy would it be to manage them away in favour of grasses and other more desirable plants?

The trip to see Dr Allen Williams that day could not have been more timely, and provided a whole host of the answers I had been seeking.

Allen was an academic, specialising in genetics, who has more recently changed tack to become a farmer. He brings an investigative and inquiring mind to the topic of mob grazing, coupled with a rigorous intellect, a habit of postulating theories, recording results and drawing sensible conclusions.

Three years ago he, and his business partner Al Smith, took on a block of CRP land. This had been within the CRP programme for 25 years which, as no grazing, cultivating or topping was allowed, had reverted to scrubland and semi-mature woodland. The first step taken by the partners was to clear the larger stems with a bulldozer. After that, they made the decision that all subsequent clearing work should be done by cattle. No more mechanical operations would be undertaken, chemical controls would be avoided and burning was out of the question.

The woodland is in the background, the cleared land in the foreground. Allen had purposely left elongated stands of trees to provide shade from the worst of the Mississippi summer and shelter in the winter

The results were nothing short of amazing! The impact was made greater because this was so much a work in progress. Land that had been properly managed by Allen for three years had transformed into lush, rich grassland in which cows grazed on shoulder high grass stands, the seeds all naturally occurring in the soil from the (at least) 25-year-old seedbank!

Allen's management had transformed the land from weed-covered scrub to dense, productive sward after only three years of mob-grazing. Incredibly, no reseeding had taken place, the clovers, grasses and other legumes were all either already in the seedbank (and had been dormant for the past 25 years+) or were carried / blown in from elsewhere.

Those pastures being exposed to only their first year of grazing were covered in weeds, mass invaders designed by nature to provide speedy ground cover, protecting the soil from the ravages of sun, wind and rain. This showed what the vegetation would look like without intensive management of the grazing (the first step towards reverting back to woodland).

After only one year of grazing, annual weeds still dominated the pasture land. More intensive grazing / trampling needed!

Next stop was to look at a pasture in its second year of grazing. Allen had concentrated the animals really tightly, encouraging them to eat all the weeds, leaves, grass and vegetation down to ground level. The perennial grasses were just starting to regrow and would quickly form a thick, dense sward, out-competing the annual weeds that had previously towered above them.

Allen had mobbed up the cattle tightly, forcing them to eat everything virtually down to the ground. There is a risk of cattle performance suffering if you ask them to do this too often, though Allen used dry cows who are better able to cope with a high roughage diet of relatively low nutritive value. As can be seen, the pasture looks more like a sheep-grazed field. This allows the sward to thicken up and it will outgrow any annual weeds this year and in future years.

As a final contrast, he also had a paddock that had been properly managed for the first three years but then for this year had been set-stocked with a group of purebred angus cattle. The sward was showing typical signs of overgrazing, with thin, bare patches interspersed with unpalatable ageing tussocks.

The set-stocked land. Bare patches interspersed with tussocks show how selective grazing allows cattle to overgraze some plants, returning time and again to eat off newly emerged leaves, whilst leaving other plants standing to seed, die and slowly oxidise. Adequate rest next year should allow the pasture to start to recover.

The variety of pastures on view was a natural result of the gradual progress Allen was making in improving the land. However, it had all the appearances of a scientific experiment, with control plots and various different 'treatments' on view. Quite fitting for a former academic!

Monday, 29 August 2011

Durwood Gordon is typical of many of the farmers I met: Observant, willing to think through problems and happy to take the road less travelled.

For example, he practices managed intensive grazing (MIG) in the summer but a more intensive mob grazing during the grass-dormant winter months. He also, against the advice of his neighbours, sowed a mixture of big bluestem and other warm-season grasses (the neighbours claimed they would be grazed out within a few years; 15 years of excellent pasture management later, they are still the dominant species in the sward).

His cattle were some of the best I saw during my travels, well adapted to their all-grass regime (Durwood farms organically) with good rumen capacity and excellent conformation. His grasslands looked productive, despite the heat of Mississippi, and he'd installed a very good infrastructure of permanent electric fences, water sources and cow tracks to make this an easy-to-operate one man system.

A drilled stand of warm season grasses that has thrived under Durwood's grazing management

An unusual flytrap used by Durwood. The dark colour replicates an animal's hide. The flies try to fly underneath the 'body' and the transparent sheets below guide them instead into a liquid-filled trap

I was fortunate enough to meet Sledge Taylor and a neighbouring farmer-friend of his, Sonny Henry, at the mob-grazing school hosted by Greg Judy in April. Somehow, I managed to get myself invited to visit Sledge's farm (he was probably too polite to refuse my request!)

Sledge is a successful cotton and cattle farmer based in Como, Mississippi. He is also a busy man, and on my arrival was in the throws of installing a huge cotton gin into his factory. Corn harvest was also about to start, cotton was in full bloom and being regularly irrigated, soybeans hung heavy with pods and he was carrying 400 cows on the farm. Despite all this, and typical of the kindness and hopsitality shown by all the people I met on this trip, he willingly gave up his whole day, and evening, to ensure I was shown all aspects of his operation.

It was fascinating. Whilst looking at his mob grazing setup, the adage "If you want something doing, ask a busy man" sprung to mind. Sledge had only visited the mob grazing school a couple of months ago but had already installed miles of fences and water pipes and was mob grazing cattle across a large part of his land.

Sledge inspecting a water connection within his recently laid water system

﻿

It was early days for the mob grazing system on Sledge's farm but already things were looking good. Lespedeza and other legumes were interspersed within the warm season grasses and the diversity is likely to increase with the longer rest periods given to the pasture land.

Mississippi is also extremely hot and humid, which further aids vegetation growth, though it does make things hard for cattle - they spend the heat of the day in the shade of the trees. One problem faced by livestock farmers in the warmer states of the US is that of endophyte-infected fescue which is toxic and exacerbates the effects of heat. Careful management of the pastures under the mob grazing regime and selective breeding of cattle are both necessary to combat its ill-effects.

A further indicator of the early success of the mob grazing was the signs of life in the soil. Dung beetle activity was visible in cow pats and there was an incredible array of grasshoppers and other insects rising in front of us as we crossed the grass fields.

Heaps of earth within the cowpat are a sure sign of dung beetle activity. They roll the manure into a ball and bury it underground, naturally cultivating the land.

Cotton farming is something new to me (not surprisingly, coming from the UK where, as I was sweltering in 98 degree F temperatures and near-100% humidity, my wife told me it was mid-60's and raining in the UK, with 'a touch of autumn in the air in the early mornings'!) I spent a fascinating few hours looking at all aspects of its production - the half-mile long centre-point irrigator on land within the Mississippi delta was particularly memorable, as was the logisitical challenge of installing a nearly-new cotton gin into a factory with the cotton harvest only weeks away.

Following a delicious steak, eaten in the enjoyable company of Sledge, his wife Denise and various neighbours at a local restaurant I retired to an old wooden house, moved 20 miles and renovated by Sledge in the last few months.

Huge programmable centre-point irrigators watered the crops growing on the Mississippi delta, driven by powerful diesel engines. The wheels on the irrigator are driven by electrical motor and operated by a pressure switch - as a wheel is activated, it moves its section of the pivot forward, thus tripping the switch of the next wheel along the boom and activating it too.

It's not mob grazing but.... cotton growing on a plant in Mississippi

A cotton harvester

The house that Sledge (re)built. In fact, he had it moved from his land on the delta, some twenty miles away. It was jacked up and transported by a specialist firm of house movers. Sledge added the veranda oncve in-situ here

Sunday, 28 August 2011

This was a popular refrain amongst ranchers and farmers practicing mob grazing: "We haven't got enough cattle at the moment".

Although no instant fix, over time mob grazing produces more grass - much more - than under conventional set-stocking regimes. It also requires animal impact, especially in the more non-brittle areas (Allan Savory came up with a brittleness scale, from 1 to 10, with one being very non brittle, humid and damp, and ten being desertlike conditions).

In a non-brittle environment (and Missouri and Mississippi were both lower down on the scale, as would be much of the UK) a lack of cattle numbers or a lack of cattle grazing density has several unintended consequences. One is that the rest period can allow weeds to proliferate in the pasture and lack of density doesn't then have the 'pasture-topping' effect that mob grazers look for from their cattle.

I saw several farms where weeds, in particular ragweed and ironweed, seemed to be shading out more desirable species. The farmers were unanimous in their opinion that, with higher stock density and grazing at the right time of year, they would be able to get the weeds under control.

If only they had more cattle....

Regrowth on a well-managed pasture on Doug Peterson's farm in North Missouri. The pasture shows an excellent mix of warm and cool season grasses and broadleaf plants and will provide excellent forage next time it's grazed, whatever the weather

During my meeting with Gabe Brown and Jay Fuhrer, they both suggested, as I was passing through Missouri, that I should try to get in touch with a guy called Doug Peterson who worked as a Grassland Conservationist with NRCS in Missouri.

Days later, I mentioned the name to Chad Peterson who, it turns out is distantly related to Doug, though neither was aware of it for the first five years of their friendship (It was their wives who finally realised they both look the same, act the same and share the same interests in mob grazing and cattle breeding. There's no escaping your genes! After some digging, they realised they shared the same Great Great (?) Grandfather on the paternal side)

As a consequence of this, I visited Doug. As well as a rewarding visit, he invited me to attend a farm walk with a group of Missouri farmers the following day, during which I met another farmer, Ben Coleman, who also invited me visit his place as I was passing. Doug also gave me the name of a geneticist-turned-farmer by the name of Allen Williams who he suggested I should meet up with in Mississippi. Subsequently, Allen gave me the name of another farmer, Durwood Gordon who I also met up with.

This is the beauty of a trip such as this, when you're meeting farmers willing to give freely of their time and their contact lists. One name, mentioned in passing, resulted in five further meetings.

Sometimes, it's true that it's not just what you know, but who you know.

Farm walks are the same the world over!

Traditional conservationists want to fence off riparian areas to prevent cattle accessing the creeks and damaging river banks. During the farm walk, we saw how, with proper management, cattle could actually improve the vegetation, helping to support the banks of the stream and thus preventing erosion. This is a creek looking as it would have done hundreds of years ago, when buffalo passed through the area intermittently. Note there is grass right up to the water's edge and small groups of trees exist in places.

Cattle grazing a pasture recently reverted from CRP land (not dissimilar to long-term setaside land in the UK). Note the large numbers of weeds in the foreground, which I comment on further in my next blog.

Chad Peterson's ranch is unlike any other I visited, posing a unique set of challenges to any farmer or rancher.

The first issue is the soil type. Chad farms in the Sand Hills area of Nebraska, where much of the higher ground is, literally, sand dunes. The fine sand is extremely unstable, and if exposed to the air will blow and wash away in moments.

The second issue is the low rainfall. Interestingly, the water table is only a few feet below the surface of his land, so water availability for cattle is not an issue - he pumps water continually into a trough for the cattle, letting surplus water run back onto the ground and into the aquifer. However, lack of rain coupled with the sandy soil means grass will only grow if managed very carefully.

This is a picture of Chad's watering system (borrowed from this website - http://handnhandlivestocksolutions.com/blog/?p=62 - as for some reason the photos I took failed to save onto my camera). Water is pumped continually, with surplus water emptying through a sumphole and down a pipe onto the previously grazed field behind the cattle.

Fortunately Chad has the skills and ability to make a success of farming under such conditions. He realised long ago - before he had heard of 'mobgrazing' or knew of anyone else who was farming like this - that allowing grass time to recover was vital. The best way he found to achieve this was to bunch the cattle up, keeping them off the majority of the land for long periods.

This allowed plants to grow a good root structure, it gave soil microbes a good food source and it encouraged the development of fungae and the excretion of glomalin into the soil, all of which help to stabilise the fine sandland.

Chad's land is to the right of the fence. Notice how, on the previously overgrazed left hand side of the fence, bare sand is showing through, whereas Chad's paddock has excellent vegetation covering and protecting the soil.

That Chad arrived at this conclusion long before anyone else was practicing (or even discussing) mob grazing demonstrates what an innovative thinker he is, coupled with great observational powers and a willingness to try new things.

He has recently turned his attention to the type of cattle he runs, and has switched breeds, preferring the hardiness of highland cattle which, he says, perfom well under the harsh climate of North Nebraska.

The highland cows and calves moving to new grazing. The calling is not typical of mob-grazed cattle but in this sitation was due to a combination of cows and calves staying 'in touch' with each other and also that Chad was making them graze down some older, less nutritious pasture. They were complaining a little, but still looked in good condition. If they'd looked over the fence at Chad's neighbours, they'd have realised the grass isn't always greener....!

The water table on Chad's ranch was a few feet below the surface of the soil. Here, he and his assistant, May, cross a small creek. Sand can be seen on the hillside in the far distance.

Farming in nature's image means trying to work in sync with nature rather than fighting it all the time. On the prairies of South Dakota, buffalo seem the obvious choice and, at the Jerde ranch, the sight of hundreds of them grazing the land was a marvellous sight.

Buffalo being moved from one paddock to the next. The siren heard in the background is the horn on Phil's old pickup, letting the buffalo know it was time to move

The Three Amigos (or at least two and a half, I managed inadvertently to self-edit my face out of the picture!)

One of the things that goes hand in hand with holistic management and mob grazing is a real interest in nature and the natural world. The whole Jerde family exhibited just such an interest, with excellent observational powers, a really good knowledge of native and introduced plant species, an understanding of the importance of the water cycle and a desire to record, with photographs and by other means, the improvements they are making to their environment.

﻿This interest means the Jerde Ranch will be in good hands for decades to come.

Phil and daughter Emily examine grasses growing in adjacent paddocks. In the foreground, heavily trampled land shows a typical combination of large amounts of litter and good, even regrowth. The animals only remained on this area of land for a day, thus avoiding damaging the plant root system.

The benefits of properly planned grazing. In the foreground is land on the Jerde Ranch, with lush green grass growing right up to the fenceline. On the far side of the fence is a neighbour's paddock, showing poor grass growth and drought stress due to overgrazing, a typical result of set-stocking the land and not giving plants sufficient rest.

The whole of the neighbouring land looked like this, despite stocking rates being much lower. I saw this pattern repeated time and again on mob-grazed land which adjoin conventionally grazed land throughout my trip.

Phil examining an individual plant which caught his eye

Examining soil on the Jerde Ranch, typical of the interest the family showed in all things related to land and the environment.

Examining a green draw high up on the prairies on the Jerde ranch

Unfortunately the sun on the lens spoils this photograph a little, but this was a big bull buffalo passing within a few feet of me on his way to new grazing. These animals are perfectly adapted to their environment.

Tuesday, 23 August 2011

It was the sight of running water that made this visit one of the most inspiring of my trip.

I was visiting Phil Jerde, his wife Jill and their nine children on their ranch in North Dakota and was being driven round the western block of their land. Now, one of the benefits of managing grassland to increase soil organic matter is that the water cycle improves. As Jay Fuhrer so abley demonstrated with his infiltration test, soil with high organic matter has great structure and absorbs water like a sponge. Conversely water struggles to penetrate low organic matter soils and so runoff and evaporation losses are much, much higher.

Phil and family have been managing their grasslands properly for a number of years now, grazing with a mixture of buffalo and cattle and giving adequate rest periods to the forage plants between grazings. Slowly, soil organic matter has been increasing. Rains are beginning to soak into the soil, being held in-situ rather than running off down hill. This water slowly seeps through the soil strata, being available to the plants for longer and gently weeping into draws (the natural valleys in the landscape).

Slowly, these draws are starting to green up. It begins with a small clump or two of warm-season (ie C4) grasses, often big bluestem or native switchgrass. Each year these clumps get larger until they start to meet and gradually the whole draw, or valley, becomes a verdent green oasis within the parched landscape.

It doesn't stop at this, though. The grasses gradually extend up the hill, as the soils improve, the water table rises and the bottom of the draw becomes damp, even in the middle of the day in 90 degree heat in August.

The ultimate sign that things are working properly is when you find, as we did, flowing water in the bottom of the draw. Getting the water flowing through the soil properly is vital whether you're in a low or high rainfall area. I am still agog at the incredible improvements Phil and his family have made to the landscape, just by managing the grazing properly.

The greening of the land. As the water cycle improves, soil becomes more water-retentive. This, coupled with an adequate rest period allows native warm-season grasses to establish once again. The line between green and brownish vegetation can clearly be seen on the side of the draw and higher on the hilltops

Big Bluestem grass in a draw on the Jerde ranch. There's a huge amount of forage here compared to the drier, shin-high material further up the hillside. What is exciting is the way the green area slowly spreads up the hill each year. I believe that one day, if Phil and his family carry on managing the land so well, the whole of his ground will be covered in dark green, tall, valuable forage.

Water lying in a draw, high up in the prairies in 90+ degree Farenheit heat

Sunday, 21 August 2011

South Dakota has vast areas of prairie land. It's dry, with less than 15 inches of rain annually, winters are freezing cold, interspersed with lethal snow blizzards, summers are scorching hot, and there are winds that blow constantly. Towns are few and far between and it's an unforgiving place to farm and graze cattle.

Consequently, as in much of upland Britain, rural communities are dying out: Youngsters see the daily grind of work their parents have to do and decide it isn't for them. They depart for the easier life of nine-to-five work in the larger towns and cities. Some retain an interest in the land, and when they inherit, will turn a few cattle out in the spring, never seeing them again until the autumn gather. Land is understocked and grass is wasted.

The Savory Institute is trying to change this. True to holistic management principles, they are working on a farming project which aims for "Triple Bottom Line" returns, namely financial, social and environmental returns. They are looking to improve the soils on the prairies, and the diversity of species (ie the environmental). They are looking to make ranching easier and more attractive to the younger generation (the social) and, of course, are looking to make it profitable once again.

With this in mind, they have joined forces with East Coast financiers John Fullerton and Larry Lunt under the banner 'Grasslands LLC'. This vehicle raises funds with a view to investing and managing ranch properties and the far-sighted investorts are focussed not only on return on capital but also on providing jobs and work for local people and in healing the land through best practice farming. (More can be read about the project at http://www.savoryinstitute.com/imported-20100211170933-home/2010/12/22/the-grasslands-story.html).

Currently they have two ranches, one in Montana which, from memory, is 30,000 acres and a second in Newell, South Dakota, which is 14,200 acres. I visited the latter and met up with manager Brandon Dalton and his assistant, Colin Boggess.

Brandon (foreground) and Colin in the middle of the prairie on Grasslands LLC's ranch outside Newell, South Dakota

Cattle are run on a planned grazing system, usually staying in paddocks for three to four days before being moved. The emphasis, as with all holistically-managed enterprises, was on giving the grazed area a rest period long enough for the plants to recover fully before being exposed to grazing again. A fully rested plant will have massive energy reserves in its roots and will be able to grow rapidly when an animal defoliates it once again. A knock-on benefit is that the rest period also allows other, slower growing species to emerge - these are often extremely attractive to livestock and in a shorter rotation get selected for and overgrazed, which eventually removes them from the sward.

Custom-grazed cattle on the Grasslands LLC ranch

The ranch was only in its second year of management and it had been an exceptionally wet year (by South Dakota standards) so whilst species diversity was increasing, it was too early to say whether this was driven entirely by management or by the year's weather pattern.

It will be interesting to follow their progress to see whether they achieve their triple bottom line goals. The visit to Phil Jerde's ranch, the following day, gave me hope that they will.

I've been doing a little research on the internet to try to understand why soil carbon and the C:N ratio is so important.

Photosynthesis
The first thing to know / remember is what happens when a plant photosynthesises which is as follows:

Sunlight hits the leaf. Within the leaf is chlorophyll which is green in colour and which acts as the catalyst for the following reaction. The plant absorbs water (usually via its roots) and carbon dioxide (usually from the air) and, using the energy from the sun, converts these two things into carbohydrate plus oxygen plus water.

Carbon dioxide + water + energy = carbohydrate + oxygen + water

or

6CO2 + 12H2O + energy (sunlight) = C6H12O6 + 6O2 + 6 H2O

It's as simple as this. A plant takes carbon dioxide out of the atmosphere and converts it into a simple sugar (a carbohydrate) which is stored within the plant to be used either as a future energy source or the carbon is used to create the 'backbone' of the plant (starches, cellulose etc). Whilst locking up the carbon, the plant emits life-giving oxygen (plants are the source of all the oxygen in the atmosphere!)

Note also that the sun's light energy is converted into chemical energy in the process. Hence, all our fossil fuels and all our biofuels are simply sunlight energy that has been captured by plants and turned into chemical energy which is then 'stored' in the plant.

Growth

When the plant grows, it pulls nutrients up from the soil as needed. For example, nitrogen is used to form proteins within a plant; potassium is used to regulate water flow and in the formation of cellulose.

Typically, the amount of carbon in a plant will be around 45% (with a range of 35%-50%). It is the nitrogen which varies and gives the C:N ratio of the plant. For example, a plant made up of 45% carbon and 5% nitrogen will have a C:N ratio of 9:1. A plant with 45% carbon and only 0.5% nitrogen will have a C:N ratio of 90:1

Decay

When a plant dies or is trampled by an animal, it will, if in moist conditions and in contact witht the soil, begin to be broken down by the different organisms in the soil. Effectively, the smaller 'bugs' in the soil eat the plant material. They need carbon and nitrogen in a specific ratio in the material they consume to enable them to grow properly.

If there is an excess of nitrogen in the plant material, they will release into the soil all that N which they don't need. However, if there is an excess of carbon in proportion to nitrogen (and 20:1 seems to be the critical level) then the bacteria will need to get some additional nitrogen from the soil to build the proteins in their bodies. This 'steals' the nitrogen from the growing plant, and is why high carbon material (eg straw, woodchip), when added to the soil, can result in a nitrogen deficiency in the following crop.

To give an idea of the C:N ratios of different materials:

Grasses are typically 20:1 to 25:1

Clover is 15:1 to 22:1

FYM is 14:1 to 20:1

Wheat/Barley/Oat stubble is 90:1 to 160:1

Lucerne hay is 12:1 to 15:1

So, if FYM is added to a soil, it will typically provide more N than the bacteria need, so some N will be available for the following plant growth.

Straw, on the other hand, will not provide enough N (in relation to the C) and hence the bacteria will have to use up soil N in order to fully break down the stubble. Therefore unless either additional N is added or (in a healthy soil) there is sufficient N available, the growing plants will show signs of nitrogen deficiency.

One final point. I mentioned that N might be available in a 'healthy' soil. What happens is that the bacteria that have eaten the plant material themselves get eaten by larger fungi and protozoa who in turn get eaten by nematodes, insects and earthworms. Each of these, as they get higher up the food chain, tend to have a higher C:N ratio in their bodies. This means that they don't need all the N (ie protein) from the smaller organism they've eaten and hence they excrete the excess into the soil where it becomes available to the plant root.

Wednesday, 17 August 2011

A delicious meal (of Schezuan beef, vegetables and rice). The bill came, with a fortune cookie on the side. The proverb inside the cookie:

"You must be the change you wish to see in the world"

I'd previously said to Jay during our meeting that I wanted to change the way UK arable farmers manage their land. Sometimes, thought-provoking material crops up at the most unexpected times and in the most unexpected places.

It was last Sunday and I'd 'awarded' myself a day off to go and look at Mount Rushmore and its carvings. On the map, it didn't look too far (it turned out to be a 430 mile, 8 hour round trip, but that's another story!)

Two hours into the trip, I got very excited because on the distant prairie I spotted some dark shapes, tightly bunched together within the vast plains.

It could only mean one thing: Someone was mob-grazing cattle.

As I got closer, things began to look a little odd. I couldn't see fences containing the animals. Also, the dark shapes I'd assumed to be black angus cattle were taking on a strange shape as I got closer. Then it dawned on me. These weren't cattle at all. And they weren't penned in by electric fence. These were bison, naturally forming into a mob as protection from predators and slowly wandering across the prairie.

For someone whose interest in mob grazing is almost becoming an obsession, it was a marvellous moment!

Bison running alongside the highway fenceline in a naturally formed mob

'Farming in Nature's Image' is a simple and very successful concept. It means working with nature, making decisions based on what would happen in the natural world if Man wasn't interfering.

Mob grazing is one example - I've already talked about the massive herds of grazing animals that used to roam the grasslands of Europe, Asia and America and which mob grazing, albeit on a small scale, tries to emulate.

The growing of cover crops is another example. Nature hates bare soil. She will do her utmost to cover it, firstly with fast growing weeds, forbs and brassicas, then with legumes and grasses and finally, if the climate is favourable, with bushes and trees. Nature also hates monocultures. They are never seen in the natural world. Instead, different species fill different micro-niches in the same area, the result being a mixture of small and tall, leafy and woody plants all occupying the same area of land.

Planting cover crops is an attempt to mimic this, and as Gabe and Jay both emphasised, the more variety the better. Within their cover-crop seed blends, they aim for a mixture of warm season broadleaves, warm season grasses, cool season broadleaves and cool season grasses, to ensure growth at different times of the year and under many different weather conditions. The ratios of each will depend on the crops grown previously, the crops to be grown afterwards, and the current levels of biological activity in the soil.

Ideally, cover crops are 'harvested' by mob-grazed animals (again, it's believed that the more variety of species - cows, sheep, hens, deer, etc - the better). A proportion of the cover crop will be trampled, forming the vital litter covering on the soil. The remainder of the cover crop will be consumed, digested and excreted as dung and urine, mixed with high numbers of microorganisms from the gut - the latter is the vital additional biology the soil needs to spring into life.

The principles of 'farming in nature's image' are simple: Look at what happens in a natural environment and use this to guide management decisions. Don't fight nature, it's so complex and has so many options, it will always win in the end. Instead, the message was clear, work with nature and you will reap dividends.

Monday, 15 August 2011

"The Burly Boys" was Neil Dennis's nickname for the team of USDA employees located at Burleigh County, North Dakota. Specifically, they work for the Natural Resources Conservation Service, or NRCS for short, with Jay Fuhrer heading up the team. They are world famous for their work in advising farmers and growers about how best to improve their soil resource. (Incidentally, Gabe Brown also sits on the district board of NRCS).

When I was researching soils for my forthcoming trip, Jay's name kept on cropping up, so frequently that in the end I decided I couldn't ignore it and had to go and meet the man.

What a stroke of luck!

Jay met us in the middle of a 7' tall field of corn (maize) - as you do - on Gabe Brown's farm and after admiring the health of Gabe's crop, he took Ray (a South Dakotan farmer who'd also visited Gabe that day to pick his brains, free of charge) and me to his office in Bismarck then onto Menoken Farm. This was at 2.30pm on a Friday afternoon and it is a measure of the man's passion for his subject that he was still with us after 7pm that night.

At his office, after meeting some other members of his team, Jay explained the importance of glomalin, the glues created by the soil organisms that creates aggregates and peds (ie smaller and larger 'clods' of soil). In a soil that is cultivated, little or no glomalin is formed. This is because the physical turning and mixing of the soil kills many of the microorganisms, smashes any structures they've been forming and lets in air which oxidises any organic matter that was present.

In fact, the only way to retain structure in a cultivated soil is to keep cultivating it. Man has to keep 'fluffing it up' with heavier and larger machines to simulate a good soil structure and thus allow the roots, and water etc to infiltrate. It's a vicious circle from which it's difficult to escape.

In a no-till or direct drill system, soil structure is formed by these glomalins holding, or glueing, each mineral particle to its neighbour. The biological activity that secretes these glomalins also creates airspaces; humus in the soil absorbs water; organic matter feeds these microorganisms. The result, once the biological activity restarts (and a conventionally tilled soil can be pretty much void of such activity and can take several years to start to recover) is that soils naturally form a well aerated, well structured shape which holds onto water and nutrients and yet is free draining too.

Jay used the 'Soil Slake Test' and 'Soil Infiltration Test' to demonstrate the difference between the two soils. (Unfortunately, I managed to forget my camera, but have found an almost identical test on youtube being demonstrated by someone else, which is attached as follows):

A Slake and infiltration test similar to the one performed by Jay Fuhrer. The major difference was that, for the slake test, Jay used three soils: A conventionally tilled soil, a no-till soil and a no-till soil that had also had animals grazing on there some time in the recent past.

The biological activity - and hence the soil's ability to hold together - was even greater in the soil which had animals grazing on it. The title of my Nuffield study "Mob grazed cattle and their potential to be the perfect arable break crop" was chosen because I have long suspected that livestock are the vital missing ingredient on all-arable farms. Jay's experiment (and the visit to Menoken Farm) demonstrated that this is indeed the case.

Jay then took us to Menoken Farm.

Menoken Farm was purchased by NRCS a few years ago as an experimental farm in which to practice what the NRCS team are preaching. Jay has been experimenting with cover crops, animal impact, mixed cropping, compost and compost teas, no till, no fertiliser, no fungicides, in fact a whole range of different things.

As Jay explained, it's all about putting carbon back into the soil. He says soil is like a bank, you must balance your withdrawals (of carbon) with your deposits. Unfortunately, for decades, farmers have been withdrawing carbon from the soil and are now totally reliant on artificial inputs to grow their crops. This is unsustainable in the medium to long term, being heavily reliant on oil and diminishing natural resources.

We need to learn how to put something back into the soil. Cover crops, and livestock, both do this very efficiently.

At Menoken Farm, Jay had a range of experiments underway. He was growing a mix of cover crops and / or cash crops. His intention was to try to find how quickly the land healed itself (with the cover crop designed to put back carbon in the soil; the animal impact designed to stimulate biological activity) and how many 'withdrawals' a farmer could make (ie growing cash crops) before more healing cover crops were needed.

Jay doesn't go anywhere without his trusty spade. Very quickly, he was digging samples from the ground, showing the difference between soils with no organic matter added and soils with just one year's cover crop.

Now the soil at Menoken was basically sand. On the untreated land, it was a pale grey colour, and fell apart at the slightest touch. There was no carbon and hence no glomalin and hence, no structure to it. Alongside it, the soil that had been cover cropped/grazed for a year was darker in colour. It was starting to hold together too, not terribly well but noticeably better than the untreated soils. And this was after just one year.

On land that had been fed and undisturbed for longer, the peds (clods) were stronger, the soil darker in colour. He was also finding that, as the soil health improved, residues broke down quicker. (I'll expand on this in my next blog).

For anyone who's interested in the subject, I suggest they read Burleigh County's Soil Conservation District Website (http://www.bcscd.com/?id=23) where there's some really valuable information.

Gabe Brown is an incredible guy. One of the reasons (but not the main reason) is found in his love and understanding of soil - or as he calls it the 'resource'. Gabe is focussed on improving the soil of his farm in North Dakota. He has a thorough understanding of what makes good soil and puts a lot of thought, time and energy into improving his 'resource'. Mob grazing is just one of the tools he uses. Cover crops are another. I will explain more in a later blog.

However, there is something else, something far greater, that makes Gabe a truly outstanding person. He advises farmers across the US on how to improve their own resource. He speaks at countless conferences; he answers emailed questions; his telephone is called twenty or thirty times a day by farmers wanting to pick his brains. And he does all this for free! He refuses to take payment, other than to cover his out of pocket expenses and is convinced that he was put on this earth to spread the message, to disseminate his knowledge to farmers and thus to improve the soil of the world.

The origins of his 'calling' lie in his experiences during his earlier years of farming. At the time, he was a conventional farmer, highly mechanised and reliant on high levels of artificial input. However, as many may remember, farming was in the doldrums and Gabe will freely admit that he was all but broke, exacerbated by losing four year's of cropping in a row as a consequence of extreme weather conditions (hail, drought etc). He reached the point where he didn't even have enough money to buy the fertiliser for the crops one year, and realised that shortly he would be out of business.

As a last throw of the dice, he planted some legumes to add natural fertility in lieu of the missing artificial fertiliser. To cut a long story short Gabe, being an observant and intelligent man, realised that the legumes not only improved fertility, but also had an impact on the soil health and consequently the water cycle. Thus began his long experiment which continues to this day.

Gabe's understanding of soil and its needs is amazing. He talks in terms of the carbon:nitrogen ratio (10:1 is optimum) and of the balance between bacteria and fungi in a soil (cultivated soils are predominantly bacterial with very little fungi - there is a strong correlation between high bacterial/low fungal levels and high incidence of crop disease; such soils also encourage annual weeds to grow, to the detriment of the crop. If we increase the soil fungi levels, the crops become cleaner and healthier). He now farms organically and is achieving yields only slightly less than conventional farmers, but with massively lower costs so his bottom line, as he openly tells anyone who asks, is (like his soils) in rude health.

Saturday, 13 August 2011

He outwinters his cattle, setting out large round hay bales in rows across the chosen fields during the preceding autumn. During the winter, electric polywire restricts the animals' access to the bales, being moved every two or three days to allow them to get to new bales. In effect the cattle are kept in a mob to consume the bales as well as the grass (which Blain has left ungrazed in that field for some months previously).

Now, I would expect that having large numbers of cattle on the land in winter would damage the sward. Also, the cattle never eat all the bale so I assumed the remaining large quantities of litter would prevent grass regrowing in these areas.

I was wrong on both counts. We inspected the field used by the cattle the previous winter and the effect was nothing short of amazing. Where the bales had lain, the grass was a rich green verdant colour, lush and sweet. Admittedly, in patches, matted hay still lay, rotting down. Blain said this would be gone by next year and in any case, he explained, it had been proven that the extra grass growth round these patches more than compensated for them.

Mob grazing in the spring and summer following also helps to remove the patches, as the hooves break up the residual hay, allowing grasses and other seeds to regrow.

The reason for the lush grass? A combination of additional fertility from the (bought in) bales, plus the extra carbon material laid down on the soil which was being converted into humus and thus aiding water retention and building organic matter.

Mob grazing is about repairing the soil. Large amounts of litter (ie plant material, not plastic bags and old newspapers) is laid down on the surface of the soil by the grazing animals as they pass through, replicating what the large grazing herds of Europe and North America did over tens of thousands of years (until man wiped them out). In fact, grassland has evolved under such conditions, namely a short period of intense grazing and trampling as the herds passed by, followed by a long rest period for regrowth.

So, large amounts of litter are laid down on the soil. Blain Hjertaas called this the 'armour' - it protects the soil from damage by rainfall, from extremes of heat and cold, from sunlight, from hoof damage. Greg Judy called it a mattress. I'd call it a mulch. I forgot to ask Neil what he called it, but you get the picture!

This is a mob-grazed field approximately ten days to two weeks after grazing. Neil's in the middle of a drought, so the alfalfa is the first to regrow. Note how deep the litter or 'armour' (or mattress' or ...)is.

When the litter's peeled back, the new grass regrowth can be seen. Within a few weeks. the litter will be buried under a sea of green grass, and it will be starting to be broken down by the worms, the bacteria, the fungi, the nematodes and all the other creepy crawlies that live in a healthy soil. It won't be long before it forms a layer of compost.

This was a clod cut at random from a field. The top inch and a half of the 'soil' was nearly all organic matter, in the process of being converted into nutrient rich, water-retentive, aerated topsoil.

One of the secrets to good mob grazing is to give the plants enough recovery time. There is no magic formula for this. Location, altitude, latitude, rainfall, temperature, cloud cover, management, etc all impact on this. Neil used to be on 90 days recovery, though as his land has improved, he's seen that come back to 60 days. Blain favours 100 days to allow all his plants to recover.

Neither of them are too concerned about seed heads either. In fact, they like to see them, for two reasons: One is that it shows the plants are fully recovered from the previous round of grazing / trampling and will have replenished their root carbohydrate stores fully. This will allow speedy regrowth post-grazing. The second reason is that seed heads are a valuable source of carbohydrate. They balance the protein lower down in the leaf and lead to excellent growth rates. A sign that the protein: energy balance was right in both Neil's and Blain's animals was that their dung was tight and well formed, not sloppy and loose (a sign of too much protein, and typical of the dung of conventionally grazed cattle).

Neil's kubota in a mature stand of grass. Note the depth of grass cover on there. 60 days ago it looked like the picture above, a layer of litter with very little green showing. Litter doesn't stop a healthy grass plant from regrowing. In fact, it maintains a suitable microclimate around the roots and encourages regrowth. Blain believes his soil remains active in the middle of a Saskatchewan winter, and as soon as the snow melts the already-warm roots help the grass plant to explode into life

The cows enjoying the mature, well grown grass

1,000 head of cattle. This is animal impact. They will move to the next strip in two and a half to three hours. There's approximately 1.2m pounds in weight of cattle grazing this strip. They're gaining weight at c.0.75kg/day though Neil believes they will get closer to 1kg/day shortly

Friday, 12 August 2011

Let's talk about fences. Many people think mob grazing means lots of time spent putting up and taking down fences, coupled with the near-constant moving of cattle.

Lets dispel a few of those myths, or at least discuss them.

The first comment to make is that if mob grazing is part of a holistic management plan (see earlier posts) then you decide how much time you want to take each day, looking after cattle. If you want to spend ten minutes moving cattle every two or three hours, (as Neil Dennis) does, then you can.

Conversely, Blain Hjertaas, also a Saskatchewan mob grazier, has made the decision to move his cattle only twice a day during the summer and only once every two to three days in the winter. (In preparation for winter, he lays out round bales of hay in rows in a paddock, restricting access using an electric fence).

A holistically-based decision must take into account the impact of that decision on three things: Its financial impact, its environmental impact and its social impact. The number of times you choose to move cattle will alter all three of these things, either for better or for worse. More frequent moves will accelerate the environmental improvements seen and will improve cattle weight gains (and hence enhance the financial results from the operation). However, there will be a negative time impact which must be considered.

Now lets look at the practicalities of moving fences.

Neil Dennis is a man who sees a problem as a challenge. For example, how do you carry all the posts you need for the electric fence for each move? How do you accurately measure the area of grass being given to the cows? How do you wind up the electric fence once the cattle have moved on? How do you cross permanent wires when on your ATV or Kubota? The answers are below.....

Neil Dennis with his modified Kubota. The red rod sticking out in front helps him to cross wires - see the video below. His home-made yellow frame carries his fencing poles and fence reel.

At the moment, Neil is winding up the reel using an electric drill (see another video, below, for an exciting clip of a drill in action!).

To put the fence out, Neil clips one end of the wire to the fence at the far end of the paddock, then drives along, unreeling the wire. After attaching and tightening it, he drives back putting in fence posts as he drives (never getting off the kubota!) The frame is designed so that all the posts are close to hand and slip off easily.

He has a GPS box attached to his kubota too. This tells him how wide his paddocks are, how long they are, what acreage they are, what shape they are etc. It doesn't yet tell him what next week's lottery numbers will be, but knowing Neil, such an invention is in the pipeline!

Neil's wire hopper. The red pole protruding from the front of Neil's Kubota hits the wire first as Neil approaches it, pushing it under the wheels of the machine. He's made sure there is nothing for the wire to snag on underneath the vehicle, and consequently can simply drive over both temporary and permanent fences without getting off his machine.

You can also see the fence posts hung on the yellow frame of the bike, to Neil's left and within easy reach as he drives along.

Neil and his drill. The easy life!

Note the donkey in the background. Neil uses this to 'train' the young cattle when they arrive. They look to the donkey for the lead, and follow him when he moves. All Neil has to do is train the donkey.

Thursday, 11 August 2011

For a brief moment, I was John Wayne, driving 1,000 head of cattle to pastures new, dust in my face, wind in my hair, cow muck on my jeans, the theme from 'Rawhide' ringing in my ears. Neil Dennis and I were moving his cattle, down the road from one paddock to another.

Tuesday, 9 August 2011

Popular convention in the UK and elsewhere says that grass should be grazed at the three-leaf stage. Beyond this, it either puts up a seedhead or, as it puts out a fourth leaf, the first one dies, so three is the magic number.

Popular convention is wrong!

Neil Dennis is a Saskatchewan farmer who runs cattle in mobs of 1,000 head. He packs them in tight and moves them every couple of hours - more on this in a later post. He's been mob grazing for a decade now and he says his land has changed out of all recognition.

One of the most noticeable changes has been to the growing patterns of his grass plant. As the mob grazing has improved the soil, the plants have been able to put down deeper roots. This has meant they are less drought prone in the 12-15" annual rainfall area that is south-eastern Saskatchewan. They also have a much longer recovery time between grazings so can develop fully.

Neil says the result is that they are no longer stressed, and a plant that isn't being stressed doesn't have to enter the reproductive phase, it can just carry on putting out new leaves. Not just any old leaves either, Neil's claims that the leaves have got broader, longer and 'juicier' (a technical term, based on the high sugar content measured using a Brix refracometer!) really appears to hold water. The picture below shows a grass plant, picked at random, from a field that had had 60 days rest.

The first leaf had indeed died off - it can be seen as the shrivelled up brown thing near the base of the stem. However, the plant had subsequently gone on to grow 13 more leaves, ALL of which were still green and busy capturing sunlight!

13 leaves! For those who are poor at maths, that's ten more than under the conventional rotational grazing practiced in the UK. So each plant has four times as much leaf area as conventional grazed ground would see. Extrapolate this up and an acre of ground being mob grazed by Neil would have 4 times the amount of feed. Juicy feed. Excellent feed.